title: First spectroscopic identification of pyrocarbonate for high CO2 flux membranes containing highly interconnected three dimensional ionic channels.
abstract: Identification of the existence of pyrocarbonate ion C2O5(2-) in molten carbonates exposed to a CO2 atmosphere provides key support for a newly established bi-ionic transport model that explains the mechanisms of high CO2 permeation flux observed in mixed oxide-ion and carbonate-ion conducting (MOCC) membranes containing highly interconnected three dimensional ionic channels. Here we report the first Raman spectroscopic evidence of C2O5(2-) as an active species involved in the CO2-transport process of MOCC membranes exposed to a CO2 atmosphere. The two new broad peaks centered at 1317 cm(-1) and 1582 cm(-1) are identified as the characteristic frequencies of the C2O5(2-) species. The measured characteristic Raman frequencies of C2O5(2-) are in excellent agreement with the DFT-model consisting of six overlapping individual theoretical bands calculated from Li2C2O5 and Na2C2O5.
authors.affiliation: Department of Mechanical Engineering, University of South Carolina, Columbia, SC 29201, USA.
authors.forename: Lingling
authors.initials: L
authors.lastname: Zhang
authors.forename: Xinyu
authors.initials: X
authors.lastname: Huang
authors.forename: Changyong
authors.initials: C
authors.lastname: Qin
authors.forename: Kyle
authors.initials: K
authors.lastname: Brinkman
authors.forename: Yunhui
authors.initials: Y
authors.lastname: Gong
authors.forename: Siwei
authors.initials: S
authors.lastname: Wang
authors.forename: Kevin
authors.initials: K
authors.lastname: Huang
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D004047:Diethyl Pyrocarbonate / Q000031:analogs & derivatives* / Q000737:chemistry; D011789:Quantum Theory; D013059:Spectrum Analysis, Raman
chemical_list: D002245:Carbon Dioxide; C079227:pyrocarbonic acid; D004047:Diethyl Pyrocarbonate